A 60-mW solid-state deep ultraviolet (DUV) laser at 193 nm with narrow linewidth is obtained with two stages of sum frequency generation in LBO crystals. The pump lasers, at 258 and 1553 nm, are derived from a homemade Yb-hybrid laser employing fourth-harmonic generation and Er-doped fiber laser, respectively. The Yb-hybrid laser, finally, is power scaling by a 2 mm × 2 mm × 30 mm Yb:YAG bulk crystal. Accompanied by the generated 220-mW DUV laser at 221 nm, the 193-nm laser delivers an average power of 60 mW with a pulse duration of 4.6 ns, a repetition rate of 6 kHz, and a linewidth of ∼640 MHz. To the best of our knowledge, this is the highest power of 193- and 221-nm laser generated by an LBO crystal ever reported as well as the narrowest linewidth of 193-nm laser by it. Remarkably, the conversion efficiency reaches 27% for 221 to 193 nm and 3% for 258 to 193 nm, which are the highest efficiency values reported to date. We demonstrate the huge potential of LBO crystals for producing hundreds of milliwatt or even watt level 193-nm laser, which also paves a brand-new way to generate other DUV laser wavelengths.

采用多级串联的主振荡放大技术，将SESAM锁模的种子光通过多级串联端泵Nd∶YVO₄晶体放大，产生平均功率为148.7 W、重复频率500 kHz~4 MHz、脉冲宽度8 ps的1 064 nm基频光，同时开展了LBO晶体高效率二倍频的研究。通过优化相位匹配，实现了平均功率为95 W的532 nm皮秒激光输出，光-光转换效率达65%，光束质量因子M_X²=1.27/M_Y²=1.42，6 h功率抖动均方根低于0.8%。该绿光皮秒激光系统具有平均功率高、转换效率高、光束质量好、稳定性高、重频可调等优点，可以被作为皮秒激光加工系统的光源，被应用于科学研究和工业加工领域。